1. Field of the Invention
An embodiment of the present invention relates to an image forming apparatus such as a copy machine, a printer, a facsimile machine, or a combined machine thereof; a detachable unit detachably attached to the image forming apparatus; and plural detachable units.
2. Description of the Related Art
For an image forming apparatus such as a copier or a printer, a technique has conventionally been known in which, for plural detachable units, corresponding connectors having corresponding different shapes are provided, so as to prevent erroneous insertions of the plural detachable units, which are detachably attached to an image forming apparatus main body (cf. Patent Document 1 (Japanese Patent Laid-Open Application No. 2007-101581)). In such an image forming apparatus, when a detachable unit (e.g., a detachable unit for a magenta color) other than a detachable unit corresponding to a specific mounting unit (e.g., a mounting unit for a black color) is attempted to be attached to the specific mounting unit, a connector of the detachable unit does not engage with a connector at the side of the main body, and thereby the erroneous insertion is prevented.
With such a conventional technique, an effect of preventing a failure in an image forming apparatus can greatly be expected. Here, the failure is such that a detachable unit is attached to a mounting unit other than the mounting unit corresponding to the detachable unit. However, when the detachable unit is attached to the mounting unit other than the mounting unit corresponding to the detachable unit, it is possible that a connector of the detachable unit and a connector at the side of the main body collide with each other without engaging with each other, and thereby the connector of the detachable unit and the connector at the side of the main body are damaged. Such a problem may not be ignored, especially when a user attempts to force a wrong detachable unit to a mounting unit.